Heater Temperature Research Articles

Heat transfer by transiently superheated fluids: Decay of unstable water-based mixtures

The present study sets out to elucidate the characteristic features of instantaneous heat transfer accompanying transient superheating of partially miscible mixtures having a lower critical solution temperature (LCST) with respect to the liquid–liquid binodal and the diffusion (liquid–liquid) spinodal. The research has employed the method of controlled pulsed heating of a wire probe, which can be used to directly measure heat flux into the medium at a strictly fixed heater temperature Tst. At a characteristic heating time of 100 ms, values of Tst were gradually increased from 100 to 500 °C, while the corresponding pressures varied from 0.1 to 35 MPa. The objects of study were aqueous solutions of PPG-425 and PPG-2000 polypropylene glycols, as well as 2,6-Lutidine, all having LCST in the range convenient for achieving large superheats. The values of the heat transfer coefficient (whose highest values reached 90 kW/m2 K for the solution with 5 wt% PPG-2000 content at the superheat degree of about 390 °C) and the energy absorbed by the solution were calculated on the basis of the primary data. The calculation results related the individual features of the studied systems to the phase diagram and characteristic system relaxation times depending on the concentration and superheat degree with respect to the spinodal. The applicability of such systems as coolants under conditions of high-power heat release for elements with a short response time is demonstrated. Based on the experimental results, we validated the selection of solutions as coolants in the concentration range from the left branch of the spinodal to the critical concentration of the solution.

Low-emissivity interior wall strategy for suppressing overcooling in radiatively cooled buildings in cold environments

Buildings with radiative cooling can significantly reduce energy consumption for cooling, but the overcooling phenomenon also occurs in cold seasons, which causes negative effects in buildings. Herein, a strategy of using low-emissivity interior surfaces to reduce the heat loss from humans to cold walls is proposed to suppress the negative overcooling effect of radiative cooling. Comparative experiments are conducted based on two small-scale boxes with internal heat sources and low/high emissivity interior surfaces. Results show that the heater temperature in the box with the low-emissivity interior surface is higher than that with the high-emissivity surface, with maximum and average temperature differences of 2.3 °C and 1.8 °C, which indicates that the radiative heat insulation effect is achieved for humans by the low-emissivity interior surface. Moreover, large-scale building modeling is performed, which not only confirms the existence of the overcooling phenomenon but also shows over 30% of heat loss can be avoided for internal heat sources by applying low-emissivity interior surfaces under overcooling conditions. Importantly, we found that interior surfaces with low emissivity under cold seasons and high emissivity under hot seasons can fully explore the potential of passive radiative cooling for buildings, which can guide the next-generation material design for energy-saving buildings.

A numerical study on bubble dynamics and heat transfer of flow boiling in an inclined microchannel

Flow boiling, as an important heat transfer method, is widely applied in many devices. In this study, a gas-liquid thermal lattice Boltzmann model is adopted to study the flow boiling in an inclined microchannel. Specifically, the bubble growth processes and heat transfer efficiency are studied for different inclined angles. The numerical results show that the liquids occur phase change almost at the same time while the inclined angles are different. As the inclined angle increases, the bubble departure time decreases. Also, the heater temperatures change periodically for the studied cases. The maximum heater temperature is not affected by the inclined angle while the minimum heater temperature decreases when the inclined angle of the microchannel increases. Therefore, the larger inclined angle increases the flow boiling heat transfer efficiency.

Investigation on the Effective Measures for Improving the Performance of Calorimetric Microflow Sensor.

The performance of the calorimetric microflow sensor is closely related to the thermal sensing part design, including structure parameter, heater temperature, and operation environment. In this paper, several measures to enhance the performance of the calorimetric microflow sensor were proposed and further verified by numerical simulations. The results demonstrate that it is more favorable to reduce the negative impact of flow separation as the space between detectors and heater is set to be 1.6 μm so as to improve the accuracy of the sensor. With an appropriate gap, the front arranged obstacle of the upstream detector can effectively widen the measure range of the sensor, benefiting from the decrease in upstream viscous dissipation. Compared to a cantilever structure, the resonances can be effectively suppressed when the heater and detectors are designed as bridge structures. In particular, the maximum amplitude of the bridge structure is only 0.022 μm at 70 sccm, which is 53% lower than that of the cantilever structure. The optimized sensor widens the range by 14.3% and significantly increases the sensitivity at high flow rates. Moreover, the feasibility of the improved measures is also illustrated via the consistency of the trend between the simulation results and experimental ones.

A bio-inspired, green, and universal preparation method to develop textile-based solar energy storage heater and ammonia leakage monitor sensor

Flexible and smart devices, especially wearable textiles, play a significant role in constantly upgrading modern healthcare and safety management. Poly(3,4-ethylenedioxythiophene) (PEDOT) has attracted much attention because of its outstanding performance, for instance, high stability, conductivity, and biocompatibility. However, PEDOT is not adaptable to the current textile industry because PEDOT has no functional groups that react with the fabrics. Herein, we have reported a facile in situ enzymatic polymerization method to prepare conductive and flexible PEDOT textiles. Polydopamine (PDA) serves as a universal adhesive to enhance the combined force of PEDOT and any fabrics, providing a secondary reaction platform for the assembly of PEDOT particles. We have polymerized conductive PEDOT on polyester-latex mesh, knitted cotton, woven wool, and polyester nonwoven fabrics with PDA treatment successfully. It should be noted that the surface temperature of the solar energy-thermal storage heater can rapidly reach 57.9 °C with 1 sun under the synergistic effect of PEDOT and PDA. In addition, PEDOT-coated ammonia gas sensor has outstanding anti-wet interference, wide detection limit, reusability, and excellent selectivity for common volatile organic compounds. This method of preparing durable coated fabrics has the potential to be widely applied in the development and design of next-generation wearable devices.

Dynamic model of a waste heat boiler

The paper discusses the experience of developing and identifying a model of a waste heat boiler as a distributed parameters plant. The waste heat boiler is considered as a heat exchanger with cross flows of interacting media. The first order hyperbolic equation acts as a mathematical model of water flow heating with a variable rate. Using the spectral method of distributed systems, a representation of the problem is obtained in the form of an expansion into a series in an orthonormalized basis, which makes it possible to represent the solution in the form of a vector-matrix model of the state space. The state-space representation is used to implement the model in a dynamic systems simulation package. The heater temperature calculation is based on the energy balance equation. The temperature of the media separator wall is determined by the heat fluxes between the exhaust gas, the wall, and the heated water. The wall temperature is assumed to be constant along the entire length of the heat exchanger. The paper presents a block diagram of the model, which takes into account the mutual influence of the wall temperatures and the heated water flow. The heat flux from the exhaust gas is calculated directly from the known parameters of the exhaust gas at the inlet and outlet of the waste heat boiler. Based on the design parameters of the heat exchanger, the dynamic characteristics of the heat transfer process are determined. The data obtained during the operation of the waste heat boiler are used to identify the heat transfer coefficient between the walls of the heat exchanger and the water flow. The result of the heat transfer coefficient identification agrees with the reference data. The article presents graphs of the original data, simulation results. It is shown that the maximum mismatch between the model and real data does not exceed two degrees, and the mean absolute error is less than 0.2 degrees.

The Impact of Pipe Ø 0,5 Heater Length and Temperature on Ovality and The Difference in Pipe Thickness for Its Bending

Ferrous metal is of material utilized mostly for many objects or kinds of stuff to help humans and their work easier. Low-carbon steel is one of the ferrous metal natures that could be utilized when transforms into more useful objects. There be cold as well as hot working to undertake. Molting by bending pipe includes cold working due to it being bent as its recrystallization temperature is lower. When the process is undertaken, the pipe dimension would be oval which needs to be examined by enumerating a lower-recrystallization temperature and whether or not to shrink the pipe ovality percentage. In addition, as the pipe is bent there would be changes in the pipe dimension because it would drives pulls as well as puts pressure on one of the cross-sectional areas so the pipe percentage of dimension/thickness changes should also be examined. Methods to apply are a series of experiments by firstly treating heating which is up to 650o C and bending pipe as its temperature goes lower between 410o C – 500o C. These two types of independent variables that differ only in their cross-sectional areas of heating also resulted in impacting on both ovality percentage and the pipe thickness of its cross-sectional area.

Clean fabrication strategy of diamond crystals containing nanocomposite films for corrosion and wear protection of AISI-321 alloy

This study focused on the synthesis of Niobium/Hexagonal-Diamond/Amorphous-Carbon (Nb/H-D: a-C) films on AISI-321 alloy. The substrate heating used as a vital deposition parameter to tailor structure of the films in an unbalanced magnetron (UB-M) sputtering system for the first time. The substrate heater temperature (Th) ranged between (RT) to 150 °C. The results indicated that increasing the substrate heater temperature promoted the abundance of hexagonal diamond (H-Diamond) crystals through the solid phase separation. Therefore, the film deposited at the highest temperature (150 °C) demonstrated the highest plenty of H-Diamond. Electrochemical impedance spectroscopy (EIS) measurements (after 2, 8, 24, 72, and 168 h immersion) and polarization tests (after 168 h immersion) disclosed that increasing the substrate heater temperature positively affects the corrosion resistance of (Nb/H-D: a-C) films. The results proved that the film deposited at the highest temperature of 150 °C, demonstrated the exceptional corrosion protection efficiency of 99.69 %. Moreover, this film presented acceptable low-frequency impedance (|Z|10KHz) and total resistance (Rt) values of >108 Ω·cm2 and >117 MΩ·cm2 at all immersion times in 3.5 wt% NaCl solution. The highest abundance of the H-Diamond phase, with remarkable chemical inertness at higher substrate heater temperatures, can be an effective reason for elevating anti-corrosion performance of the films. Additionally, as the substrate heater temperature enhanced from RT to 150 °C, mechanical properties illustrated an remarkable increment trend (increasing hardness from 20 to 32.7 GPa and the elasticity modulus from 407 to 470 GPa). Moreover, the anti-wear performances of the films significantly improved with increasing substrate heater temperature, reducing the wear rate from 9.4 × 10−6 to 9 × 10−7 mm3/N·m. These results are mainly attributed to the highest abundance of the superhard H-Diamond phase in the film deposited at higher substrate heater temperature. In conclusion, the (Nb/H-D: a-C) film synthesized at 150 °C represented a promising candidate for tailoring the electrochemical and anti-wear performances of AISI-321 alloy.

Numerical Simulation of Conjugate Mixed Convection in 3D Channel with Heat-Generating Flat Element and Symmetrical Solid Two-Fin System

This paper presents the numerical simulation results of conjugate mixed convection in a three-dimensional channel with a heat-generating element and solid fins. It should be noted that the symmetrical location of fins has been studied. The system of partial differential equations, presented in dimensionless form using velocity and vorticity vectors, has been solved by the finite difference method on a uniform grid. The central difference schemes have been used to approximate diffusive terms. In contrast, for an approximation of convective terms, the monotonic Samarskii difference schemes have been applied to improve the stable properties of central differences of the second order of accuracy. Analysis has been performed on a wide range of governing parameters, including the Reynolds number (200 ≤ Re ≤ 1000), the material of the fins (aluminum, copper, and iron), and the location of the fins on the heater surface, taking into account the identical distances between the fins and the nearest walls. Water has been considered a working cooling medium. The obtained outcomes characterize the most efficient heat removal from the surface of the energy source using the considered fin system. For example, by using copper fins, the cooling efficiency of the heating element can be increased. The average heater temperature decreases significantly with an increase in the Reynolds number. The distance between the fins also makes a significant contribution to the cooling phenomenon. It is noted that with the most successful choice of location, it is possible to decrease the temperature of the heater by more than 12%.

Flexible Transparent Planar Heater Comprising ZnO/Cu/Al2O3

In this study, we fabricated transparent heaters composed of an ultrathin Cu-layer heating element sandwiched between a ZnO underlayer and an Al2O3 overlayer. With the Cu layer thickness fixed at 8.5 nm, the thicknesses of the ZnO and Al2O3 layers were independently varied to reach the optimum antireflecting condition (maximum transmittance of 88.3% and average visible light transmittance of 79.8% were achieved). The sheet resistances for the ZnO/Cu/Al2O3 heaters can be varied by simply modulating the Cu layer thicknesses. In order to assess the flexibility of the transparent heaters, we constructed a ZnO/Cu/Al2O3 structure on flexible polyimide substrates, and the thermal, electrical, optical and mechanical characteristics were evaluated. Because of the planar heating element of the Cu layer, the thermal response was found to be extremely high, i.e., less than 10 s were required to reach 90% of the target temperatures. Once the target temperatures were reached, the heater temperatures were highly stable with no degradation of electrical and optical properties. Furthermore, the heating capability was maintained under severe mechanical deformation, e.g., at a bending radius of 4 mm. The structure also exhibited highly sustainable optoelectronic properties under repetitive mechanical deformation, confirming the potential for commercialization. Finally, we demonstrated that ZnO/Cu/Al2O3 rolled around a human finger exhibited highly uniform heating characteristics, rendering the heaters suitable for wearable, healthcare electronics.

Application of an Automated System for Converting Waste Cooking Oil into Aromatherapy Candles

This research focuses on the development of an automated system for the production of aromatherapy candles using waste cooking oil. The study addresses the challenges faced in small-scale production, including limited capacity, manual processes, and inconsistent product quality. To overcome these challenges, an automated machine is proposed to improve efficiency and productivity. The homogenization process and heating time were identified as critical areas for improvement. A sequential control system was successfully implemented, enabling the conversion of waste cooking oil into aromatherapy candles with a production capacity of 10.5 liters per unit run. The motor control system utilized On-Off control with modified power input to minimize vibration issues, operating the motor at 50-60 RPM. The temperature heater control system employed a PID control method, specifically the Ziegler-Nichols type 2 method, with Kp and Ki values of 247.5 and 1.104, respectively. The chosen PID parameters demonstrated satisfactory performance, including a rise time of 22.95 minutes, maximum overshoot of 2.85%, and a dead time of 510 seconds. The implemented system was controlled using an Arduino controller, ensuring a fast response and stable operation.

Analysis of intake air temperature effect on performance of portable atmospheric water generation (PAWG) systems with heat sink angle orientation of 75o

The increasing demand for clean water and the diminishing supply of clean water sources can result in a clean water crisis. Air is a ubiquitous, inexpensive, and clean water source. Using Atmospheric Water Generators (AWG), the water contained in the air can be extracted. This study's objective was to determine the effect of inlet air temperature and air heater power variations on tool performance and PAWG condensate water production at a condenser angle of 75 degrees. The procedure utilized is experimental on three PAWG boxes. Each box has a distinct temperature at its entrance. The variation of inlet air temperature is accomplished by heating the air before it enters the box with an air heater; the applied power variations are 0.484 Watt, 0.964 Watt, and 1.702 Watt. The results demonstrated that variations in air heater power and inlet air temperature affected system performance and condensate water production. Maximum water discharge and PAWG performance were achieved when the air heating power was 0.48 watts and the water discharge was 1.166 milli liters per hour. At 0.0084 ml/h/W, the PSys system performance had the highest value. The variable air heating power of 0.946 Watt represents the utmost COP value of PAWG. This power variable has a high temperature difference and influences the COP value at high levels.

Effect of damping coefficients on a free-piston Stirling engine under a constant power condition based on a thermodynamic-dynamic coupled model

The Free Piston Stirling Engine (FPSE) is a complex system, in which the transient behaviors of its thermal and dynamic characteristics are coupled. To examine the strong coupling system under constant heating power and evaluate the effect of damping coefficients on engine performance, prediction of the aforementioned characteristics is essential. To this end, this study develops an FPSE system model based on quasi-static thermodynamics and piston dynamics to determine the thermal performance of the working fluid and the dynamic behavior of the displacer and piston, and the model is validated on the Re-1000. Then, the model is applied to examine the influence of the damping coefficients of two pistons on reactor core heater temperature, power, efficiency, amplitude, frequency, and phase angle under constant power condition. The results indicate that the model can well capture the transient behaviors of thermal and dynamic characteristics at Re-1000. After 0.7 s, the engine reaches a steady-state operation. Under the constant heating power of 3000 W, the displacer and piston damping significantly affect the engine's performance. Four displacement damping coefficient points are specified, and the piston damping coefficient changes in the range of Cp = 500 ∼ 1600Ns/m. As a result, the heater's stable working-point temperature changes from 590 K to 1060 K leading to an increase in indicated power from 1000 W to approximately 1500 W. The displacer and piston amplitudes show an increasing and decreasing trend respectively, with a decreasing trend in frequency and phase angle, but enhanced heat transfer performance. The dynamic-thermodynamic coupling model provides an opportunity to instantly calculate the open-loop response of the FPSE, which is a reference for future FPSE power-load matching designs.

Insights into the thermo-hydraulic properties of compacted MX80 bentonite during hydration under elevated temperature

In high-level radioactive waste geological repositories, compacted bentonite undergoes coupled thermo-hydraulic processes due to heat released from a central waste canister and groundwater imbibition from the surrounding host rock. An understanding of these processes is essential for long-term simulations of radionuclide migration and canister corrosion, which requires an understanding of temperature effects on the coupled thermo-hydraulic properties governing these processes. In this study, a tank-scale radial infiltration test was used to investigate water imbibition processes in compacted bentonite under a central heater temperature of 200 °C that simulates high thermal gradients in a repository. Interpretation of this test focuses on evaluation of the liquid water wetting front during hydration and the interpretation of the temperature-dependent transient soil water retention curve (SWRC), thermal conductivity function (TCF), and hydraulic conductivity function (HCF). The SWRC during imbibition follows a temperature-dependent wetting path. Temperature effects on the hydraulic conductivity of bentonite in saturated conditions had the greatest effect on the shape of the HCF, with minimal temperature effects at higher suctions. The transient thermal conductivity data matched well with a new TCF linked with the SWRC shape. Although the bentonite layer was restrained, local deformations during hydration may have affected the shapes of the TCF and HCF.

IoT enabled smart solar water heater system using real time ThingSpeak IoT platform

AbstractThis dissertation aims to reuse the cold water which will initially present inside the water heater and reduce its wastage by sending it back to the water tank. The water heater temperature could be customized based on the number of users either manually or in an automated way using Internet of Things (IoT) techniques. The system is designed and operated using open‐source hardware and an IoT platform. The smart solar water heater with IoT capabilities continuously monitors the tank level, temperature, and pH level, and the data collected by the IoT node is uploaded/published to ThingSpeak. The IoT cloud analyses the sensor value and instructs the control unit of the smart solar system. The IoT enabled solar water heating system efficiency is high for smart homes and Industry 4.0. The main advantages of this model include handling multiple users, reducing the wastage of cold water, and purifying the water based on TDS level and this model aims to make it possible to control the proposed system from anywhere and at any time. The highest efficiency of the respective solar water heater could be well utilized.

Study on the Deposition Characteristics of Molybdenum Thin Films Deposited by the Thermal Atomic Layer Deposition Method Using MoO2Cl2 as a Precursor

In this study, we conducted research on manufacturing molybdenum (Mo) thin films by a thermal atomic layer deposition method using solid MoO2Cl2 as a precursor. Mo thin films are widely used as gate electrodes and electrodes in metal-oxide semiconductor field-effect transistors. Tungsten (W) has primarily been used as a conventional gate electrode, but it suffers from reduced resistivity due to the residual fluorine component generated from the deposition process. Thus, herein, we developed a Mo thin film with low resistivity that can substitute W. The MoO2Cl2 precursor used to deposit the Mo thin film exists in a solid state. For solid precursors, the vapor pressure does not remain constant compared to that of liquid precursors, thereby making it difficult to set process conditions. Furthermore, the use of solid precursors at temperatures 600 °C and above has many limitations. Herein, H2 was used as the reactive gas for the deposition of Mo thin films, and the deposition temperature was increased to 650 °C, which was the maximum processing temperature of the aluminum nitride heater. Additionally, deposition rate, resistivity change, and surface morphology characteristics were compared. While resistivity decreased to 12.9 μΩ∙cm with the increase of deposition temperature from 600 °C to 650 °C, surface roughness (Rq) was increased to 0.560 nm with step coverage of 97%. X-ray diffraction analysis confirmed the crystallization change in the Mo thin film with increasing process temperature, and a certain thickness of the seed layer was required for nucleation on the initial wafer of the Mo thin film. Thus, the molybdenum nitride thin film was deposited after the 4 nm deposition of Mo thin film. This study confirmed that crystallinity of Mo thin films must be increased to reduce their resistivity and that a seed layer for initial nucleation is required.

Convective heat transfer in a thermal chimney for freshwater production in geothermal total flow systems

The convective heat transfer of air in a laboratory-scale thermal chimney with rectangular cross-section of constant area and two row electrical heaters simulating two heat exchangers was studied experimentally and numerically at 60–200 ℃ nominal temperatures of the top row heaters, 100 ℃ of the low row heaters and 20 ℃ ambient temperature to verify our design concept on freshwater production in geothermal total flow systems. Computational fluid dynamics simulations of air convective heat transfer were performed in ANSYS 2019R CFX based on the three-dimensional, steady Reynolds-averaged Navier-Stokes equations, Boussinesq buoyancy model, k-ω turbulence model, and energy equation. The thermal radiation between heater surfaces and chimney walls was considered. The overall thermal and heat transfer characteristics, temperature and flow fields in the chimney were obtained. Effects of boundary condition of heater surface and thermal radiation between two row heaters on heat transfer were discussed. The thermal characteristics of the chimney with two row heaters are better than that with single row heaters. The predicted thermal power and convective Nusselt number agree with the experimental data, and the convective Nusselt number of the low row heaters is enhanced by (11.6–29.8) % compared with the single row heaters. The optimal operating nominal temperature of top row heaters should be higher than 140 ℃, and the optimal centre-to-centre row gap ratio is 5. Multiple jets in the gaps among the heaters and temperature jump crossing each row were observed. The maximum velocity and temperature jump rise with increasing heater nominal temperature.

The development of APIO : Solar Power Plant Based Technology for Automatic Fish Dryer Equipment

APIO is a fish drying equipment that utilizes sunlight which is converted into electrical energy using a solar power plant. This dryer works automatically using a control system that can control temperature and weight in predetermined settings. APIO designed in the form of a closed box with a heater and fan using a battery as an energy source. APIO uses a load cell and thermocouple as control input using an Arduino microcontroller and regulates the heat temperature in the box between 40-50?C. This tool was tested in the Pasie Nan Tigo Padang, Sumatra Barat. APIO tested using the Arduino uno control at night from 23:00 to 03:15 using fish weighing 5108 grams, data collection was carried out once for 15 minutes for 18 times. The average heater temperature was 32.71?C and the outside temperature was 25?C. The heater voltage was 11.33 V and the heater current was 36.02 A with clear weather conditions. The test results showed a decrease in fish weight to 4208 grams dry. Day time tested from 13:00 to 15:15 using fish weighing 1012 grams, taking data once for 15 minutes for 10 times the average heater temperature is 43.85?C, outside temperature is 30?C and fish weight reaches 208 grams dry.

Nanocrystalline gallium nitride electron transport layer for cesium lead bromide photovoltaic power converter in blue light optical wireless power transmission

Nanocrystalline gallium nitride (nc-GaN) layers were deposited by RF magnetron sputtering for the electron transport layer of the cesium lead bromide (CsPbBr3) photovoltaic power converter. We investigated the structural and electrical properties of the nc-GaN layers and found that substrate heater temperature is a key factor to determine the electrical conductivity of the nc-GaN layers. CsPbBr3 photovoltaic power converters with nc-GaN electron transport layers show good photovoltaic performance. The best performance was obtained at the substrate heater temperature of 550 °C and a conversion efficiency of 5.56% (V OC = 1.24 V, J SC = 6.68 mA cm−2, FF = 0.66) under AM1.5 G illumination with a light intensity of 100 mW cm−2. The estimated conversion efficiency under blue light with a wavelength of 450 nm is 28.8%.

Leidenfrost limit enhancement via supersonically sprayed iron carboxylate framework for convection cooling

Device cooling schemes are required to reduce the local temperature of solar panels and solar air heaters, while maintaining their radiative heat to maximize energy conversion. Therefore, an efficient cooling scheme was developed using textured surfaces augmented by highly porous materials for increasing their total surface area. In this study, highly porous iron carboxylate framework, MIL-100(Fe), Materials of Institute Lavoisier, was introduced to substrates to provide a highly textured surface. This significantly reduced the temperature of the surface that was subject to radiative heat during both air and mist (or aerosol) cooling. In the case of mist cooling, the proposed MIL-100(Fe)-coated substrates were superhydrophilic, which promoted close contact between the impacting aerosols and the heated surface. Single drop impact and evaporation experiments were conducted to quantify the rate of heat removal provided by the proposed MIL-100(Fe) coatings. These coatings provided an increase in the Leidenfrost limit from 140 to 200 °C. As such, the highly wettable and porous MIL-100(Fe)-coated layers promoted rapid evaporative cooling. The proposed layers were analyzed using scanning electron microscopy, x-ray diffraction, atomic force microscopy, and Brunauer–Emmett–Teller data to elucidate the reason for their increased heat transfer rate.